A vulnerability was found in Linux Kernel. It has been declared as problematic. Affected by this vulnerability is the function follow_page_pte of the file mm/gup.c of the component BPF. The manipulation leads to race condition. The attack can be launched remotely. It is recommended to apply a patch to fix this issue. The identifier VDB-211921 was assigned to this vulnerability.

A vulnerability classified as critical was found in Linux Kernel. Affected by this vulnerability is the function l2cap_reassemble_sdu of the file net/bluetooth/l2cap_core.c of the component Bluetooth. The manipulation leads to use after free. It is recommended to apply a patch to fix this issue. The associated identifier of this vulnerability is VDB-211087.

A vulnerability has been found in Linux Kernel and classified as problematic. This vulnerability affects the function inet6_stream_ops/inet6_dgram_ops of the component IPv6 Handler. The manipulation leads to race condition. It is recommended to apply a patch to fix this issue. VDB-211090 is the identifier assigned to this vulnerability.

Race condition in the install_user_keyrings function in security/keys/process_keys.c in the Linux kernel before 3.8.3 allows local users to cause a denial of service (NULL pointer dereference and system crash) via crafted keyctl system calls that trigger keyring operations in simultaneous threads.

In the Linux kernel, the following vulnerability has been resolved: wireguard: receive: annotate data-race around receiving_counter.counter Syzkaller with KCSAN identified a data-race issue when accessing keypair->receiving_counter.counter. Use READ_ONCE() and WRITE_ONCE() annotations to mark the data race as intentional. BUG: KCSAN: data-race in wg_packet_decrypt_worker / wg_packet_rx_poll write to 0xffff888107765888 of 8 bytes by interrupt on cpu 0: counter_validate drivers/net/wireguard/receive.c:321 [inline] wg_packet_rx_poll+0x3ac/0xf00 drivers/net/wireguard/receive.c:461 __napi_poll+0x60/0x3b0 net/core/dev.c:6536 napi_poll net/core/dev.c:6605 [inline] net_rx_action+0x32b/0x750 net/core/dev.c:6738 __do_softirq+0xc4/0x279 kernel/softirq.c:553 do_softirq+0x5e/0x90 kernel/softirq.c:454 __local_bh_enable_ip+0x64/0x70 kernel/softirq.c:381 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline] _raw_spin_unlock_bh+0x36/0x40 kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:396 [inline] ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline] wg_packet_decrypt_worker+0x6c5/0x700 drivers/net/wireguard/receive.c:499 process_one_work kernel/workqueue.c:2633 [inline] ... read to 0xffff888107765888 of 8 bytes by task 3196 on cpu 1: decrypt_packet drivers/net/wireguard/receive.c:252 [inline] wg_packet_decrypt_worker+0x220/0x700 drivers/net/wireguard/receive.c:501 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2706 worker_thread+0x525/0x730 kernel/workqueue.c:2787 ...

A race condition flaw was found in the Linux kernel sound subsystem due to improper locking. It could lead to a NULL pointer dereference while handling the SNDCTL_DSP_SYNC ioctl. A privileged local user (root or member of the audio group) could use this flaw to crash the system, resulting in a denial of service condition

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: Fix potential data-race in __nft_obj_type_get() nft_unregister_obj() can concurrent with __nft_obj_type_get(), and there is not any protection when iterate over nf_tables_objects list in __nft_obj_type_get(). Therefore, there is potential data-race of nf_tables_objects list entry. Use list_for_each_entry_rcu() to iterate over nf_tables_objects list in __nft_obj_type_get(), and use rcu_read_lock() in the caller nft_obj_type_get() to protect the entire type query process.

A race condition was found in the GSM 0710 tty multiplexor in the Linux kernel. This issue occurs when two threads execute the GSMIOC_SETCONF ioctl on the same tty file descriptor with the gsm line discipline enabled, and can lead to a use-after-free problem on a struct gsm_dlci while restarting the gsm mux. This could allow a local unprivileged user to escalate their privileges on the system.

Race condition in kernel/events/core.c in the Linux kernel before 4.9.7 allows local users to gain privileges via a crafted application that makes concurrent perf_event_open system calls for moving a software group into a hardware context. NOTE: this vulnerability exists because of an incomplete fix for CVE-2016-6786.

A use-after-free flaw was found in the Linux Kernel due to a race problem in the unix garbage collector's deletion of SKB races with unix_stream_read_generic() on the socket that the SKB is queued on.

A race condition was found in the Linux Kernel. Under certain conditions, an unauthenticated attacker from an adjacent network could send an ICMPv6 router advertisement packet, causing arbitrary code execution.

A race condition was found in the Linux kernel's IP framework for transforming packets (XFRM subsystem) when multiple calls to xfrm_probe_algs occurred simultaneously. This flaw could allow a local attacker to potentially trigger an out-of-bounds write or leak kernel heap memory by performing an out-of-bounds read and copying it into a socket.

In the Linux kernel, the following vulnerability has been resolved: net: bridge: use DEV_STATS_INC() syzbot/KCSAN reported data-races in br_handle_frame_finish() [1] This function can run from multiple cpus without mutual exclusion. Adopt SMP safe DEV_STATS_INC() to update dev->stats fields. Handles updates to dev->stats.tx_dropped while we are at it. [1] BUG: KCSAN: data-race in br_handle_frame_finish / br_handle_frame_finish read-write to 0xffff8881374b2178 of 8 bytes by interrupt on cpu 1: br_handle_frame_finish+0xd4f/0xef0 net/bridge/br_input.c:189 br_nf_hook_thresh+0x1ed/0x220 br_nf_pre_routing_finish_ipv6+0x50f/0x540 NF_HOOK include/linux/netfilter.h:304 [inline] br_nf_pre_routing_ipv6+0x1e3/0x2a0 net/bridge/br_netfilter_ipv6.c:178 br_nf_pre_routing+0x526/0xba0 net/bridge/br_netfilter_hooks.c:508 nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline] nf_hook_bridge_pre net/bridge/br_input.c:272 [inline] br_handle_frame+0x4c9/0x940 net/bridge/br_input.c:417 __netif_receive_skb_core+0xa8a/0x21e0 net/core/dev.c:5417 __netif_receive_skb_one_core net/core/dev.c:5521 [inline] __netif_receive_skb+0x57/0x1b0 net/core/dev.c:5637 process_backlog+0x21f/0x380 net/core/dev.c:5965 __napi_poll+0x60/0x3b0 net/core/dev.c:6527 napi_poll net/core/dev.c:6594 [inline] net_rx_action+0x32b/0x750 net/core/dev.c:6727 __do_softirq+0xc1/0x265 kernel/softirq.c:553 run_ksoftirqd+0x17/0x20 kernel/softirq.c:921 smpboot_thread_fn+0x30a/0x4a0 kernel/smpboot.c:164 kthread+0x1d7/0x210 kernel/kthread.c:388 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 read-write to 0xffff8881374b2178 of 8 bytes by interrupt on cpu 0: br_handle_frame_finish+0xd4f/0xef0 net/bridge/br_input.c:189 br_nf_hook_thresh+0x1ed/0x220 br_nf_pre_routing_finish_ipv6+0x50f/0x540 NF_HOOK include/linux/netfilter.h:304 [inline] br_nf_pre_routing_ipv6+0x1e3/0x2a0 net/bridge/br_netfilter_ipv6.c:178 br_nf_pre_routing+0x526/0xba0 net/bridge/br_netfilter_hooks.c:508 nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline] nf_hook_bridge_pre net/bridge/br_input.c:272 [inline] br_handle_frame+0x4c9/0x940 net/bridge/br_input.c:417 __netif_receive_skb_core+0xa8a/0x21e0 net/core/dev.c:5417 __netif_receive_skb_one_core net/core/dev.c:5521 [inline] __netif_receive_skb+0x57/0x1b0 net/core/dev.c:5637 process_backlog+0x21f/0x380 net/core/dev.c:5965 __napi_poll+0x60/0x3b0 net/core/dev.c:6527 napi_poll net/core/dev.c:6594 [inline] net_rx_action+0x32b/0x750 net/core/dev.c:6727 __do_softirq+0xc1/0x265 kernel/softirq.c:553 do_softirq+0x5e/0x90 kernel/softirq.c:454 __local_bh_enable_ip+0x64/0x70 kernel/softirq.c:381 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline] _raw_spin_unlock_bh+0x36/0x40 kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_tt_local_purge+0x1a8/0x1f0 net/batman-adv/translation-table.c:1356 batadv_tt_purge+0x2b/0x630 net/batman-adv/translation-table.c:3560 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703 worker_thread+0x525/0x730 kernel/workqueue.c:2784 kthread+0x1d7/0x210 kernel/kthread.c:388 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 value changed: 0x00000000000d7190 -> 0x00000000000d7191 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 14848 Comm: kworker/u4:11 Not tainted 6.6.0-rc1-syzkaller-00236-gad8a69f361b9 #0

In the Linux kernel, the following vulnerability has been resolved: pmdomain: mediatek: fix race conditions with genpd If the power domains are registered first with genpd and *after that* the driver attempts to power them on in the probe sequence, then it is possible that a race condition occurs if genpd tries to power them on in the same time. The same is valid for powering them off before unregistering them from genpd. Attempt to fix race conditions by first removing the domains from genpd and *after that* powering down domains. Also first power up the domains and *after that* register them to genpd.

jbd2_journal_wait_updates in fs/jbd2/transaction.c in the Linux kernel before 5.17.1 has a use-after-free caused by a transaction_t race condition.

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dpu: Add mutex lock in control vblank irq Add a mutex lock to control vblank irq to synchronize vblank enable/disable operations happening from different threads to prevent race conditions while registering/unregistering the vblank irq callback. v4: -Removed vblank_ctl_lock from dpu_encoder_virt, so it is only a parameter of dpu_encoder_phys. -Switch from atomic refcnt to a simple int counter as mutex has now been added v3: Mistakenly did not change wording in last version. It is done now. v2: Slightly changed wording of commit message Patchwork: https://patchwork.freedesktop.org/patch/571854/

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix race condition between session lookup and expire Thread A + Thread B ksmbd_session_lookup | smb2_sess_setup sess = xa_load | | | xa_erase(&conn->sessions, sess->id); | | ksmbd_session_destroy(sess) --> kfree(sess) | // UAF! | sess->last_active = jiffies | + This patch add rwsem to fix race condition between ksmbd_session_lookup and ksmbd_expire_session.

In the Linux kernel before 5.17.3, fs/io_uring.c has a use-after-free due to a race condition in io_uring timeouts. This can be triggered by a local user who has no access to any user namespace; however, the race condition perhaps can only be exploited infrequently.

A use-after-free flaw was found in the Linux kernel’s PLP Rose functionality in the way a user triggers a race condition by calling bind while simultaneously triggering the rose_bind() function. This flaw allows a local user to crash or potentially escalate their privileges on the system.

A race condition was found in the Linux kernel's watch queue due to a missing lock in pipe_resize_ring(). The specific flaw exists within the handling of pipe buffers. The issue results from the lack of proper locking when performing operations on an object. This flaw allows a local user to crash the system or escalate their privileges on the system.

In the Linux kernel, the following vulnerability has been resolved: spi: Fix null dereference on suspend A race condition exists where a synchronous (noqueue) transfer can be active during a system suspend. This can cause a null pointer dereference exception to occur when the system resumes. Example order of events leading to the exception: 1. spi_sync() calls __spi_transfer_message_noqueue() which sets ctlr->cur_msg 2. Spi transfer begins via spi_transfer_one_message() 3. System is suspended interrupting the transfer context 4. System is resumed 6. spi_controller_resume() calls spi_start_queue() which resets cur_msg to NULL 7. Spi transfer context resumes and spi_finalize_current_message() is called which dereferences cur_msg (which is now NULL) Wait for synchronous transfers to complete before suspending by acquiring the bus mutex and setting/checking a suspend flag.

In the Linux kernel, the following vulnerability has been resolved: KVM: s390: vsie: fix race during shadow creation Right now it is possible to see gmap->private being zero in kvm_s390_vsie_gmap_notifier resulting in a crash. This is due to the fact that we add gmap->private == kvm after creation: static int acquire_gmap_shadow(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page) { [...] gmap = gmap_shadow(vcpu->arch.gmap, asce, edat); if (IS_ERR(gmap)) return PTR_ERR(gmap); gmap->private = vcpu->kvm; Let children inherit the private field of the parent.

In the Linux kernel, the following vulnerability has been resolved: scsi: ufs: core: Fix racing issue between ufshcd_mcq_abort() and ISR If command timeout happens and cq complete IRQ is raised at the same time, ufshcd_mcq_abort clears lprb->cmd and a NULL pointer deref happens in the ISR. Error log: ufshcd_abort: Device abort task at tag 18 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000108 pc : [0xffffffe27ef867ac] scsi_dma_unmap+0xc/0x44 lr : [0xffffffe27f1b898c] ufshcd_release_scsi_cmd+0x24/0x114

A use-after-free vulnerability was found in network namespaces code affecting the Linux kernel before 4.14.11. The function get_net_ns_by_id() in net/core/net_namespace.c does not check for the net::count value after it has found a peer network in netns_ids idr, which could lead to double free and memory corruption. This vulnerability could allow an unprivileged local user to induce kernel memory corruption on the system, leading to a crash. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although it is thought to be unlikely.

In the Linux kernel, the following vulnerability has been resolved: net: nfc: fix races in nfc_llcp_sock_get() and nfc_llcp_sock_get_sn() Sili Luo reported a race in nfc_llcp_sock_get(), leading to UAF. Getting a reference on the socket found in a lookup while holding a lock should happen before releasing the lock. nfc_llcp_sock_get_sn() has a similar problem. Finally nfc_llcp_recv_snl() needs to make sure the socket found by nfc_llcp_sock_from_sn() does not disappear.

In the Linux kernel, the following vulnerability has been resolved: spi: sun6i: fix race between DMA RX transfer completion and RX FIFO drain Previously the transfer complete IRQ immediately drained to RX FIFO to read any data remaining in FIFO to the RX buffer. This behaviour is correct when dealing with SPI in interrupt mode. However in DMA mode the transfer complete interrupt still fires as soon as all bytes to be transferred have been stored in the FIFO. At that point data in the FIFO still needs to be picked up by the DMA engine. Thus the drain procedure and DMA engine end up racing to read from RX FIFO, corrupting any data read. Additionally the RX buffer pointer is never adjusted according to DMA progress in DMA mode, thus calling the RX FIFO drain procedure in DMA mode is a bug. Fix corruptions in DMA RX mode by draining RX FIFO only in interrupt mode. Also wait for completion of RX DMA when in DMA mode before returning to ensure all data has been copied to the supplied memory buffer.

In the Linux kernel, the following vulnerability has been resolved: mm/sparsemem: fix race in accessing memory_section->usage The below race is observed on a PFN which falls into the device memory region with the system memory configuration where PFN's are such that [ZONE_NORMAL ZONE_DEVICE ZONE_NORMAL]. Since normal zone start and end pfn contains the device memory PFN's as well, the compaction triggered will try on the device memory PFN's too though they end up in NOP(because pfn_to_online_page() returns NULL for ZONE_DEVICE memory sections). When from other core, the section mappings are being removed for the ZONE_DEVICE region, that the PFN in question belongs to, on which compaction is currently being operated is resulting into the kernel crash with CONFIG_SPASEMEM_VMEMAP enabled. The crash logs can be seen at [1]. compact_zone() memunmap_pages ------------- --------------- __pageblock_pfn_to_page ...... (a)pfn_valid(): valid_section()//return true (b)__remove_pages()-> sparse_remove_section()-> section_deactivate(): [Free the array ms->usage and set ms->usage = NULL] pfn_section_valid() [Access ms->usage which is NULL] NOTE: From the above it can be said that the race is reduced to between the pfn_valid()/pfn_section_valid() and the section deactivate with SPASEMEM_VMEMAP enabled. The commit b943f045a9af("mm/sparse: fix kernel crash with pfn_section_valid check") tried to address the same problem by clearing the SECTION_HAS_MEM_MAP with the expectation of valid_section() returns false thus ms->usage is not accessed. Fix this issue by the below steps: a) Clear SECTION_HAS_MEM_MAP before freeing the ->usage. b) RCU protected read side critical section will either return NULL when SECTION_HAS_MEM_MAP is cleared or can successfully access ->usage. c) Free the ->usage with kfree_rcu() and set ms->usage = NULL. No attempt will be made to access ->usage after this as the SECTION_HAS_MEM_MAP is cleared thus valid_section() return false. Thanks to David/Pavan for their inputs on this patch. [1] https://lore.kernel.org/linux-mm/994410bb-89aa-d987-1f50-f514903c55aa@quicinc.com/ On Snapdragon SoC, with the mentioned memory configuration of PFN's as [ZONE_NORMAL ZONE_DEVICE ZONE_NORMAL], we are able to see bunch of issues daily while testing on a device farm. For this particular issue below is the log. Though the below log is not directly pointing to the pfn_section_valid(){ ms->usage;}, when we loaded this dump on T32 lauterbach tool, it is pointing. [ 540.578056] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 540.578068] Mem abort info: [ 540.578070] ESR = 0x0000000096000005 [ 540.578073] EC = 0x25: DABT (current EL), IL = 32 bits [ 540.578077] SET = 0, FnV = 0 [ 540.578080] EA = 0, S1PTW = 0 [ 540.578082] FSC = 0x05: level 1 translation fault [ 540.578085] Data abort info: [ 540.578086] ISV = 0, ISS = 0x00000005 [ 540.578088] CM = 0, WnR = 0 [ 540.579431] pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBSBTYPE=--) [ 540.579436] pc : __pageblock_pfn_to_page+0x6c/0x14c [ 540.579454] lr : compact_zone+0x994/0x1058 [ 540.579460] sp : ffffffc03579b510 [ 540.579463] x29: ffffffc03579b510 x28: 0000000000235800 x27:000000000000000c [ 540.579470] x26: 0000000000235c00 x25: 0000000000000068 x24:ffffffc03579b640 [ 540.579477] x23: 0000000000000001 x22: ffffffc03579b660 x21:0000000000000000 [ 540.579483] x20: 0000000000235bff x19: ffffffdebf7e3940 x18:ffffffdebf66d140 [ 540.579489] x17: 00000000739ba063 x16: 00000000739ba063 x15:00000000009f4bff [ 540.579495] x14: 0000008000000000 x13: 0000000000000000 x12:0000000000000001 [ 540.579501] x11: 0000000000000000 x10: 0000000000000000 x9 :ffffff897d2cd440 [ 540.579507] x8 : 0000000000000000 x7 : 0000000000000000 x6 :ffffffc03579b5b4 [ 540.579512] x5 : 0000000000027f25 x4 : ffffffc03579b5b8 x3 :0000000000000 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: Fix a race condition of vram buffer unref in svm code prange->svm_bo unref can happen in both mmu callback and a callback after migrate to system ram. Both are async call in different tasks. Sync svm_bo unref operation to avoid random "use-after-free".

In the Linux kernel, the following vulnerability has been resolved: fs/proc/task_mmu: move mmu notification mechanism inside mm lock Move mmu notification mechanism inside mm lock to prevent race condition in other components which depend on it. The notifier will invalidate memory range. Depending upon the number of iterations, different memory ranges would be invalidated. The following warning would be removed by this patch: WARNING: CPU: 0 PID: 5067 at arch/x86/kvm/../../../virt/kvm/kvm_main.c:734 kvm_mmu_notifier_change_pte+0x860/0x960 arch/x86/kvm/../../../virt/kvm/kvm_main.c:734 There is no behavioural and performance change with this patch when there is no component registered with the mmu notifier. [akpm@linux-foundation.org: narrow the scope of `range', per Sean]

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to truncate meta inode pages forcely Below race case can cause data corruption: Thread A GC thread - gc_data_segment - ra_data_block - locked meta_inode page - f2fs_inplace_write_data - invalidate_mapping_pages : fail to invalidate meta_inode page due to lock failure or dirty|writeback status - f2fs_submit_page_bio : write last dirty data to old blkaddr - move_data_block - load old data from meta_inode page - f2fs_submit_page_write : write old data to new blkaddr Because invalidate_mapping_pages() will skip invalidating page which has unclear status including locked, dirty, writeback and so on, so we need to use truncate_inode_pages_range() instead of invalidate_mapping_pages() to make sure meta_inode page will be dropped.

A race condition was found in the way the Linux kernel's memory subsystem handled the copy-on-write (COW) breakage of private read-only shared memory mappings. This flaw allows an unprivileged, local user to gain write access to read-only memory mappings, increasing their privileges on the system.

In the Linux kernel, the following vulnerability has been resolved: tls: fix race between async notify and socket close The submitting thread (one which called recvmsg/sendmsg) may exit as soon as the async crypto handler calls complete() so any code past that point risks touching already freed data. Try to avoid the locking and extra flags altogether. Have the main thread hold an extra reference, this way we can depend solely on the atomic ref counter for synchronization. Don't futz with reiniting the completion, either, we are now tightly controlling when completion fires.

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: fix race condition on enabling fast-xmit fast-xmit must only be enabled after the sta has been uploaded to the driver, otherwise it could end up passing the not-yet-uploaded sta via drv_tx calls to the driver, leading to potential crashes because of uninitialized drv_priv data. Add a missing sta->uploaded check and re-check fast xmit after inserting a sta.

A race condition was found in the Linux kernel's bluetooth device driver in {min,max}_key_size_set() function. This can result in a null pointer dereference issue, possibly leading to a kernel panic or denial of service issue.

A race condition was found in the Linux kernel's net/bluetooth in {conn,adv}_{min,max}_interval_set() function. This can result in I2cap connection or broadcast abnormality issue, possibly leading to denial of service.

A race condition was found in the Linux kernel's media/dvb-core in dvbdmx_write() function. This can result in a null pointer dereference issue, possibly leading to a kernel panic or denial of service issue.

Race condition in Google Chrome before 25.0.1364.97 on Windows and Linux, and before 25.0.1364.99 on Mac OS X, allows remote attackers to cause a denial of service or possibly have unspecified other impact via vectors related to media.

A race condition was found in the Linux kernel's scsi device driver in lpfc_unregister_fcf_rescan() function. This can result in a null pointer dereference issue, possibly leading to a kernel panic or denial of service issue.

A use-after-free read flaw was found in sock_getsockopt() in net/core/sock.c due to SO_PEERCRED and SO_PEERGROUPS race with listen() (and connect()) in the Linux kernel. In this flaw, an attacker with a user privileges may crash the system or leak internal kernel information.

A race condition was found in the Linux kernel's sound/hda device driver in snd_hdac_regmap_sync() function. This can result in a null pointer dereference issue, possibly leading to a kernel panic or denial of service issue.

A race condition was found the Linux kernel in perf_event_open() which can be exploited by an unprivileged user to gain root privileges. The bug allows to build several exploit primitives such as kernel address information leak, arbitrary execution, etc.

An out-of-bounds read flaw was found in the Linux kernel’s TeleTYpe subsystem. The issue occurs in how a user triggers a race condition using ioctls TIOCSPTLCK and TIOCGPTPEER and TIOCSTI and TCXONC with leakage of memory in the flush_to_ldisc function. This flaw allows a local user to crash the system or read unauthorized random data from memory.

A use-after-free vulnerability was found in the Linux kernel in drivers/net/hamradio. This flaw allows a local attacker with a user privilege to cause a denial of service (DOS) when the mkiss or sixpack device is detached and reclaim resources early.

A use-after-free flaw was found in the Linux kernel’s sound subsystem in the way a user triggers concurrent calls of PCM hw_params. The hw_free ioctls or similar race condition happens inside ALSA PCM for other ioctls. This flaw allows a local user to crash or potentially escalate their privileges on the system.

A flaw was found in pfn_swap_entry_to_page in memory management subsystem in the Linux Kernel. In this flaw, an attacker with a local user privilege may cause a denial of service problem due to a BUG statement referencing pmd_t x.

An issue found in linux-kernel that leads to a race condition in rose_connect(). The rose driver uses rose_neigh->use to represent how many objects are using the rose_neigh. When a user wants to delete a rose_route via rose_ioctl(), the rose driver calls rose_del_node() and removes neighbours only if their “count” and “use” are zero.

In the Linux kernel, the following vulnerability has been resolved: nbd: fix race between nbd_alloc_config() and module removal When nbd module is being removing, nbd_alloc_config() may be called concurrently by nbd_genl_connect(), although try_module_get() will return false, but nbd_alloc_config() doesn't handle it. The race may lead to the leak of nbd_config and its related resources (e.g, recv_workq) and oops in nbd_read_stat() due to the unload of nbd module as shown below: BUG: kernel NULL pointer dereference, address: 0000000000000040 Oops: 0000 [#1] SMP PTI CPU: 5 PID: 13840 Comm: kworker/u17:33 Not tainted 5.14.0+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) Workqueue: knbd16-recv recv_work [nbd] RIP: 0010:nbd_read_stat.cold+0x130/0x1a4 [nbd] Call Trace: recv_work+0x3b/0xb0 [nbd] process_one_work+0x1ed/0x390 worker_thread+0x4a/0x3d0 kthread+0x12a/0x150 ret_from_fork+0x22/0x30 Fixing it by checking the return value of try_module_get() in nbd_alloc_config(). As nbd_alloc_config() may return ERR_PTR(-ENODEV), assign nbd->config only when nbd_alloc_config() succeeds to ensure the value of nbd->config is binary (valid or NULL). Also adding a debug message to check the reference counter of nbd_config during module removal.